what are the maximum length of PHP variable/function/class name?

Please if you know, make a r开发者_如何学运维esponse. thanks

I couldn't find an answer but this

http://www.php.net/manual/en/userlandnaming.php

Says

However, there are some pretty sexy characters in there should you be looking for a unique namespace which is not too lengthy

I think if you're worried about being too long for the compiler, it's way too long for a human.